Teachers

As I understand it, they are evaluated on how well their students do on standardized tests. Granted, a teacher can be stuck with uncooperative students who don't want to learn, but presumingly this happens to all teachers so she is graded relative to her peers.

One thing that makes teachers different is tenure, where once a teacher has been employed a certain time it's almost impossible to fire them. They have no incentive to do a good job because their job is secure no matter how poorly they do it. This makes no sense.